Roller box for lathes



Nov. 27, 1945. c. s. HARRIS ROLLER BOX FOR LATHES Filed May' 15, 1944Patented Nov. 27, 1945 OFFICE ROLLER. BOX FOR LATHES Claud S. Harris,Cirencester, England Application May 13, 1944, Serial No. 535,470 InGreat Britain April 16, 1943 7 Claims.

This invention relates to roller boxes for lathes. The object of theinvention is the provision of improvements in roller boxes for latheswhich will make it possible to t the cutting tool, and to remove andreplace it say for grinding, more easily and with the exercise of lessskill than heretofore.

The invention consists broadly of a roller box for lathes, comprising ahead adapted to move axially relative to the workpiece, a slide mountedon said head so as to be adjustable in a true straight line transverselyof the axis of said workpiece, clamping means for clamping a cuttingtool in said slide at a fixed accurately determined orientation, withsaid cutting tool transverse to the workpiece and transverse to the lineof adjustment of said slide, said cutting tool being adjustable,relative to said slide, in a direction longitudinally of itself whensaid clamping means are loosened, a setting block xedly mounted on saidhead, said setting block having a setting face accurately ground in aplane which is parallel to the line of adjustment of said slide, andsuch that, when said cutting tool is adjusted longitudinally of itselfrelative to said slide, so as to abut against said setting face, saidcutting tool will always be at the correct longitudinal adjustment, twofurther slides mounted on said head so as each to be adjustable nearerto, and further from, the axis of the workpiece, and two rollersrotatably mounted on said slides respectively with their axes parallelto the axis of the workpiece, whereby said rollers may be adjusted toengage the periphery of the cut workpiece to support it against thethrust exerted by the cutting tool.

In order that the invention may be the more clearly understood, a rollerbox in accordance therewith will now be described, reference being madeto the accompanying drawing, wherein:

Figure l is an end elevation of said roller box looking in the directiontowards which said roller box is adapted to be fed when cutting;

Figure 2 is a sectional side elevation of the same on line Ae-B ofFigure 1;

Figure 3 is a sectional plan on line C-D of Figure 1;

Figure 4 is a section on line E-F of Figure 1 showing the clamping meansfor the cutting tool.

Referring to the drawingthe cutting tool IV is adapted to be fed in adirection axially of the rotating workpiece 2, so that it engages saidworkpiece from one end towards the other and reduces its diameter to therequired amount.

.LoOkng at Figure 2 the cutting tool I will be fed from left to right.As shown, said cutting tool I is orientated tangentially to theworkpiece with one corner of its edge Ia forming the cutting point Ib.

Said cutting tool I is vcarried and fed by a feed head 3 and this feedhead has rotatably mounted on it, with their axes parallel to the axisof the workpiece, two bearing rollers 4 and 5, whose peripheries areadapted to engage the periphery of the workpiece, after it has been cutby the cutting tool, and thereby support said workpiece in opposition tothe thrust exerted by said cutting tool. which are co-planar, are set asmall distance rearwardly of the cutting point Ib of the cutting tool sothat they engage the surface of the workpiece only after it has beencut.

Said cutting tool is mounted in a slide 6 which is adjustable relativeto the feed head 3l in a direction transversely of said cutting tool Iso as to be capable of adjusting the latter towards and away from theaxis of the workpiece-2, and YSaid cutting tool is capable of beingadjusted, relative to said slide, in a direction longitudinally ofitself, to such a position that the cutting point Ib of said cuttingtool may be brought by said slide into vcorrect tangential engagementwith said workpiece. For all diameters of workpiece, the longitudinaladjustment of the cutting tool in the slide 6 should always be the same,and it is a feature of the invention that a setting block is xedly andpermanently mounted on the feed head 3,.which setting block has anaccurately ground setting face 'la such that, when the cutting end ofthe cutting tool I abuts against said setting face, the longitudinaladjustment of said cutting tool in said slide is correct. Actually saidseting face 'la is in a plane which is radial with respect to the axisof the workpiece.

The mounting of said cutting tool in the slide 6 is such that theorientation of said cutting tool must always be accurately the same toensure that whatever the diameter of workpiece 2 being y cut--that is tosay whatever the degree of overlap l depending on the material beingcut.

In addition, the line of adjustment of the slide Thus these rollers 4and 5,

the feed'head'3.

6 is accurately parallel to the plane of the setting face 'Ia so that,once the cutting tool has been adjusted with its edge Ia in abutmentwith the setting face la, the adjustment of said slide will leave saidedge and cutting face in abutment.

In the construction shown, the workpiece being assumed horizontal, thesetting block 'I is 1ocated above the workpiece with the setting face'Ia vertical. VThe .cutting tool `I is therefore also above the`workpiece .and it is orientated horizontally. Said cutting tool I ishowever not orientated exactly at right angles to the axis .of theworkpiece but is inclined with its cutting end slightly forwards at anangle of say `7 as best shown in Figure 3.

The rollers 4 and 5 are mounted on respective slides 8 and 9 which areadjustable relative tio the feed head 3 closer to, or further:Erom,.tlf1ev axis of the workpiece. 'I'he roller 4 is adapted to engagethe workpiece diametrically opposite' tothe inutting )point Ib. Thisroller is thus with .its axis vertically underneath the axis of theworkpiece .and its slide t8 moves accurately in a, vertical straightline. f

lChe other'roller 5 Ais spaced from the roller 4 .the direction ofrotation of the workpiece. In practice theslid-e S of .this .roller-..5is adjustable in a horizontal-line, which is radial with respect totheaxis of the workpiece. Y

The cutting tool I is of strictly uniform square or rectangular .crosssection. 'For mounting said cutting ltool in the slide .6, the `latter.comprises a separate elongated cradle I for receiving said cuttingtool. This cradle 1:0 has an upwardly facing horizontal surface .Ila onwhich 4the bot-l V- tom horizontal face of the cutting tool rests and arearwardly facing verticalsurface I-0b against which vthe front verticalface -of said cutting tool rests. Theundersurface Hic-of said cradle isincl-ined and res-ts on -a similar-ly inclined surface 6a of the slideproper, the inclination being in such -a sense that 'downward pressureon said cradle Ieca-uses lthe -same to 'move rearwardly with respect tosaid slide 6. The rear vertical face of said cutting -tool rests againstAa forwardly facing vertical surface 6b of the slide proper. The cutting-tool I is held down in the cradle by means of two screws II in Atappedholes Yin Athe slide proper l6, which screws press dow-n on the topsurface of fsaid cutting tool, and i-t will be seen A4tliat `-the moretightly Athese screws are screwed up, not on-l-y will the bottom face of-said cut-ting *tool -be 'the more `tightly pressed against thehorizontal surface Ia of the cradle, but,

owing tothe two inclined vsurfaces Ic and 6a.,

the-'rear face of -said cutting tool will be -pressed the more tight-lyagainst the vertical surface -Gb of the slide proper.

As stated the slide 6 is mounted so as `to be-adjusta-ble *in a 'truevertical line with respect to -Bol-ts I2 are -provided'for'clamping saidslide to said head 3 when the former is set to the required position.

vFor effecting the vertical adjustment of the Aslide relative 'to thehead, a iine adjustment device 'of the micrometer ltype is provided.Thus a screwed bolt I3 extends upwardly from, `and rigidly with, Vsaidslide, and mates with a nut I4 which is rotatable Yrelative to the headbut fixed in respect of -axial movement. This nut has a calibratedlscale and is provided with a milled flange for finger'operation.

Describing now the const-ructional details, the feed head 3 is generally`in the form v.of -a th-ick plate in a plane at right `anglesto-thevax-isA ofthe workpiece. From the rear face of said feed head aboss 30 co-axial with the workpiece extends. As shown, said head 3 has ahole` through it for giving access to the workpiece, which hole extendsinto the boss. Extending rearwardly from the boss 3i] is a tubularextension 3|. The boss is partly cut away as indicated at 32. The headis mounted by the boss 30 and extension 3I on the usual feeding slide.as will be .understood by those skilled in the art.

The slide 6 is formed with a vertical rib or tongue I5 (Figure 3)projecting from its rear face, and this tongue I5 engages slidingly in acorresponding vertical groove in the front face of the head 3., .saidtongue and groove being accurately cut 'to ensure true vertical movementof `the slide. Said slide is held with the tongue in place inthe grooveby means of the two bolts I2. These pass completely through respectiveholes in the slide, and through a Vertical slot I2a in fthe fhead :3 andthrough holes in ,a clamping plate 'I6 .at the back .of .the head. Nutsil [are .screwed .on to the bolts I2 :at the :back of this .clampingplate. .andthe bolts 42 at their front iends are termed with straightsided heads :L3 whichllie in grooves .the front face lof the slide 6 asshown, whereby the bolts are prevented from turning.

`ilori.preventing the nut I4 from Amoving axially itis :formed with Va.downwardly depending reduced neck I8 (Figure 12) at the lower -end .ofwhich is a .flange 20. vA horizontal plate V2l is secured :on athe .topof .the head 3, said .platelbeing formed with a slotthrough it throughwhich passesisaid neck I9. VThe upper surface of the Iiiange lbearsagainst lthe .lower surface of the plate S2I andthe lowerlsur-face ofthenut 441i rnediately above the )neck -I^3 bears against the uppersurface lof said plate V24 and thus sai-d .nut yis capable of v.rotatingwhile being constrained against Aaxial movement.

'Theslide 8 on which the rolle-r 1I is mounted is accurately out andslides in an accurately cut vertical groove '2.2 in lthe front face .ofthe head `:i as show-n. Said slide is fheld in place 'in said .groove by:means :of -a `bol-t -23 passing through a hole :said Jslide andthrou'gha -vertical slot 24 -inlthe head and :having on its rearwardlyprojeoting end la nut 25 and washer 26. To adjust said slide said nut isloosened and saidsl-ide 'is -s'lid up Aor down by the Ilingers, the Vnutbeing tightened aga-'1n to clamp the slide in place when -it'is-correotlyadjusted. Vfllf-ie'bol't 23 ls-prevented trom turning lbyYa straight sided head 21 at @its lliront-end which flies in agroovein-the front face of the slide 8 as shown.

The slide 9 'ismonn-ted and-adjusted linthesarne way as the slide 8 andno -further vdescription `thereof isdeemed necessary.

tThe setting block 'I -is -an lL-shaped member as shown, Ione limb ofthe 1yL is secured against the iront 'face of the head in an accuratelyLfitting vertical groove 28 -by means vof Aa screw i9. The

Yother limb 'of the -L stands out from `the front face of the head 3andthe surface rIaisformed cn this latter -l-imb.

The cross sectional shape of the cradle 1B, :and `the -detai'ls of thehorizontal slot in the from face -of the Aslide t, which receives 4saidcradle and the ycutting tool -I, `are deemed lclear from lthe -drawling.It :will V:be appreciated that the cradle i0 is entirely lfree from theslide except Ifor the clampy-ing effect ofthe screws JII -asheretoforedescribed.

ope-ration the Jscrews 'II are first 'loosened andthe cuttingtool I-isadiustedlwith respect -to the slide B so that its edge la abutsagainst the setting face Ia (with a lfeeler of say .010 of an inch inbetween). Said cutting ytool is then clamped to theslide Ii by means ofthe'screws II, and the slide is adjusted vertically by the micrometernut I4 until, by trial and error',l the workpiece 2 isvcut to thecorrect diameter. The slide 6 is then clamped to the head 3 by means ofthe nuts I'I on the screws I2. The rollers 4 and 5 are then adjusted bymeans of their slides 8 and "9 against a short cut surface of theworkpiece, and are clamped in place, whereupon the device is set.

If it is desired to remove and replace the cutting tool I (say forgrinding) without changing the setting, said cutting tool is unclampedfrom its slide 6 and removed endways, and when it is replaced it canimmediately be reset against the setting face la. When a diameter lessthan `a certain amount is being cut, the edge la of said cutting tool Iwill be clear of the setting face 1a, and it will then be necessary tonote the reading of the micrometer nut I4 at the set position, so that,for re-setting the tool I after removal, the slide '6 can be upwardlyadjusted so that the tool can be Set against the Setting face as before,after which the micrometer nut is again screwed to the originally notedposition.

What I claim and desire to secure by Letters Patent is:

1. A roller box for lathes, comprising a head adapted to move axiallyrelative to the workpiece, a slide mounted on said head so as to beadjustable in a, true straight line transversely of the axis of saidworkpiece, clamping means for clamping a cutting tool in said slide at afixed accurately determined orientation, with said cutting tooltransverse to the workpiece and transverse to the line of adjustment ofsaid slide, said cutting tool being adjustable, relative to said slide,in a direction longitudinally of itself by unclamping and reclampingsaid clamping means, a setting block mounted on said head, said settingblock having a setting face accurately ground in a plane which isparallel to the line of adjustment of said slide, and such that, whensaid cutting tool is adjusted longitudinally of itself relative to saidslide, so as to abut against said setting face, said cutting tool vwillalways be at the correct longitudinal adjustment, two further slidesmounted on said head so as each to be adjustable nearer to, and furtherfrom, the axis of the workpiece, and two rollers rotatably mounted onsaid slides respectively with their axes parallel to the axis of theworkpiece, whereby said rollers may be adjusted to engage the peripheryof the cut workpiece to support it against the thrust "exerted by thecutting tool.

2. A roller box according to claim l, wherein the plane of the settingface of the setting block is radial with respect to the axis of theworkpiece.

3. A roller box according to claim l, and in which the cutting tool isof uniform rectangular cross section, wherein the means for clampingsaid cutting tool in said slide comprise a slot or keyway formed in saidslide having a surface parallel to the line of adjustment of said slide,and an elongated L-section cradle located in said slot or keyway, saidcutting tool being located with two adjacent faces flush against the twoinner surfaces of said L-section cradle and with a third face flushagainst one of the surfaces of said slot or keyway, screw means beingprovided for exerting pressure on the fourth surface of said cuttingtool, thereby pressing the opposite outer surface of said cradle flushagainst a second surface of said slot or keyway, and said last named twosurfaces being so inclined that the pressure of the one on the other, bya cam action, forces said cradle towards the first named surface of saidslot or keyway.

'4. In a lathe construction, a head adapted to move axially relative tothe workpiece, a slide mounted on saidA head so as to be adjustable in atrue straight line transversely of the axis of said workpiece, clampingmeans for clamping a cutting tool in said slide at a fixed accuratelydetermined orientation, with said cutting tool transverse to theworkpiece and transverse to the line of adjustment of said slide, saidcutting tool being adjustable, relative to said slide, in a directionlongitudinally of itself by unclamping and reclamping said clampingmeans, and a setting block mounted on said head, said setting blockhaving a setting face accurately ground in a plane which is parallel tothe line of adjustment of said slide, and such that, when said cuttingtool is adjusted longitudinally of itself relative to said slide, so asto abut against said setting face, said cutting tool will always be atthe correct longitudinal adjustment.

5. In a lathe construction, a head adapted to move axially relatively tothe workpiece, a slide mounted on said head so as to be adjustabletransversely of the axis of the workpiece, clamp ing means for clampinga cutting tool of uniform rectangular cross section in said slide at afixed accurately determined orientation, with said cutting tooltransverse to the workpiece and transverse to the line of adjustment ofsaid slide, said clamping means comprising al slot or keyway formed insaid slide having a surface parallel to the line of adjustment of saidslide, and an elongated L-section cradle located in said slot or keyway,said cutting tool being located with two adjacent-I faces ush againstthe two inner surfaces of said L-section cradle and with a third faceflush against one of the surfaces of said slot or keyway, screw meansbeing provided for exerting pressure on the fourth surface of saidcutting tool, thereby pressing the opposite outer surface of said cradleflush against a second surface of said slot or keyway, and said lastnamed two surfaces being so inclined that the pressure of the one on theother, by a cam action, forces said cradle towards the first namedsurface of said slot or keyway,

6. In a lathe construction, a carrier for a cutting tool of uniformrectangular cross section, and means for clamping said cutting tool insaid carrier at an accurately determined orientation, said clampingmeans comprising a slot or keyway formedv in said carrier, and anelongated L-section cradle located in said slot or keyway, said cuttingtool being located with two adjacent faces flush against the two innersurfaces of said L-section cradle and with a third face flush againstone of the surfaces of said slot or keyway, screw means being providedfor exerting pressure on the fourth surface of said cutting tool,thereby pressing the opposite outer surface of said cradle flush againsta second surface of said slot or keyway, and said last named twosurfaces being so inclined that the pressure of the one on the other, bya cam action, forces said cradle towards the rst named surface of saidslot or keyway,

7. In a lathe construction, a carrier for an elongated cutting toolhaving at least three plane faces, and means for clamping said cuttingtool in said carrier at an accurately determined orientation, said meanscomprising a recess formed in said carrier and having at least two planesurfaces, `and an AI -seofzian .cradle =located :in snd recess, said.cutting tool `being xlucated with two adjacent faces flush `bhe.imonner sum.- faces of said L-section cradlemd with a ithind face flushagainst one ef `saidz-suurfaces of said e recess, screw means beingginovided lor pressure .on :said cuttingmool in Asuch Aa direction

